Hi
It's confusing.
As far as I can see this feature becomes active in the export dialogue if you select an export resolution (AR) that differs from the AR of your project. Then gives you the choice of either shrinking the frame down to fit (letterbox) or cropping to the selected values and zooming to fit.
If all your clips are 16:9 then for all 16:9 export resolution values the option is inactive. If you try to export at a none 16:9 export AR then the option becomes active.
What I do find confusing however is if, for example I zoom into a clip that is not 16:9 and set the zoom at 16:9 or crop to 16:9 and then export the clip at a 16:9 resolution the option remains active. I not sure why this happens. Using automatch here chops the image up.
e,g, Here is an image placed on the timeline ..............
The next step was to crop it to a 16:9 AR.....
So far so good. Exporting this with a 16:9 resolution is OK......... the letterbox option is active however and the output is letterboxed ..nevertheless the export is WYSIWYG..........
If the export AR is Automatch content and force 16:9 the result is the same as above
BUT if just Auto match content is used that is where it becomes confusing........
This is the letterboxed version. I can see that the original format is present but the cropped area is not exact.
Choosing the Crop and zoom option,,,(you have to use one of them in this scenario if you use auto match 16:9) gives this...........
This even more confusing.:o but if I think hard I can see what is happening. However it's not exactly what I originally had in mind. The export will have the letterbox feature active in this scenario. Why..the preview is 16:9 the image (cropped) is 16:9 and I would have expected a 16:9 export just like the preview. Letterbox is not exact as there is still a narrow border. Trying to force 16:9 using automatch has the same result but without forcing that AR it's not good...
I think this is where users are confused..(I know I am) WYS IS not WYG. This is with a single image on the timeline; there may also be some confusing output if the timeline clips are all different AR as then the AR isn't the same for all clips and the permutations become a bit complex. I think I can see where NCH are coming from but its not intuitive. :wacko:
Nat